The present invention generally relates to techniques and devices for measuring vapor emission, and more particularly to test kits and methods for measuring vapor emission from a planar surface. The invention has particular application in quantifying vapor emission from concrete floors prior to installing a floor covering.
Floors that emit excessive moisture will detrimentally affect a floor covering installation. For this reason, floor manufacturers typically specify maximum allowable vapor emission for each specified flooring material offered by the manufacturer. For example, normal allowable vapor emission for sheet vinyl and hardwood floors is 3 pounds, where "pounds" indicates the measured weight of moisture emitted from 1,000 square feet of floor over a 24-hour period. The limit for vinyl composition tile (VCT) is typically 5 pounds. Some carpeting can withstand vapor emission levels up to about 7 pounds.
In the flooring industry, calcium chloride kits have become widely used for taking measurements of vapor emission from concrete floors prior to installing a floor covering. Such kits typically consist of a plastic "petri dish" containing about 30 grams of calcium chloride, a substance having good moisture absorption properties, and a larger cover which during a test is placed on the floor over the calcium chloride filled petri dish. Heretofore, the cover component of the test kit has been fabricated of a thin, clear plastic material that resembles a square or rectangular cake pan with a flange around the edge. Such prior test kit covers typically have a footprint of about 70 to 72 square inches and a height of about 11/2 inches and are sealed to the floor using a putty-like sealing material, such as butyl, in order to maintain airtight contact with the floor. The difficulty with these kits is that they are cumbersome to install, requiring absolute cleaning of all particulate matter from the floor, and meticulous pressing around the edge to achieve an airtight seal around the entire cover perimeter. Also, after the test is completed the sealant must be peeled off the floor, which normally leaves a residue which must be removed. The pre-cleaning, the placement and retrieval of the cover, and post-test cleaning of residue from the floor's test surface can consume 20 minutes or more for each vapor emission test.
Another drawback of conventional calcium chloride test kit designs is that the test kit is not reusable, since the cover is destructibly removed after test. Thus, with conventional kit designs a new test kit is typically used for each measurement, with no opportunity for recycling.
The present invention overcomes the above-mentioned disadvantages of conventional calcium chloride test kits, by providing a test kit and method for measuring vapor emission from concrete floors and other planar surfaces using test kit components that are reusable. The invention further provides a vapor emission test kit that simplifies the placement and retrieval of the test kit from the test surface, eliminates the need to clean the test surface after use, and generally reduces the amount of time required to set up and conclude a test.